Too often an enterprise initiates plans for replacing existing hardware, software, or systems including hardware and/or software when the vendor of such components ceases to support its product. The date when a vendor ceases to support its product may be defined as the product's end of life. Initiating a replacement plan for a component at its end of life results in an interruption due to the unavailability of the component and a replacement for it to individuals and/or systems dependent upon the component.
To avoid these interruptions, some enterprises initiate a replacement plan for the component at the component's retirement date. The retirement date occurs before the end of life and is determined by the end of life less the amount of time needed to acquire a replacement component, install and test it, and move all necessary files and data, if any, onto it such that there is no interruption due to the transition from the existing component to its replacement for individuals and/or systems dependent on the component. For example, Mar. 1, 2007 may be the end of life for a particular server. Acquiring a suitable replacement for that server, installing and testing the replacement, and moving files and data from the existing server to the replacement server may require two months to perform. Thus, it is necessary to initiate acquisition of the replacement server on Jan. 1, 2007, the retirement date of the existing server, in order to prevent interruptions due to the unavailability of the existing server and its replacement.
Although initiating a replacement plan for a component at its retirement date eliminates interruptions caused by unavailability of the component, delaying action until the retirement date may still be economically undesirable. As a component nears its end of life, its vendor may begin to charge more for continued support of the component that will soon be obsolete. Thus, the cost to the enterprise for maintaining the existing component begins to rise. At some point in time thereafter, the maintenance cost for the existing component may exceed a similar cost for a suitable and available replacement component. If so, the enterprise begins to lose money beyond this date by continuing to maintain the existing component when a suitable replacement with a lower maintenance cost is available.